.btn-enter{
  opacity: 0;

  transform: translateX(100%)
}

.btn-enter:active{
  opacity: 1;
  transition: opacity 300ms;

  transform: translateX(0)
}

.btn-exit{
  opacity: 1;
}

.btn-exit-active{
  opacity: 0;
  transition: opacity 300ms;

  transform: translateX(-100%)
}